1. Field of the Invention
The invention is generally directed to the field of laser vision correction, and more particularly, to laser vision correction systems and control apparatus and methods.
2. Description of Related Art
Ultraviolet laser systems and related methods are known for enabling ophthalmic surgery on the cornea in order to correct vision defects. Techniques for ablative photodecomposition include, but are not limited to, LASIK, LASEK, and PRK. Conventional treatment by these techniques is typically indicated for refractive defects including myopia, hyperopia, and presbyopia, with or without astigmatism. In some cases, re-treatment from a previous surgery is also indicated.
Although surgeons administer the ophthalmic treatment, it is typically the laser manufacturers who program their lasers with tissue ablation algorithms to effect suitable treatment for the various diagnosed refractive defects. As used herein, the term xe2x80x9ctissue ablation algorithmxe2x80x9d refers to the process or procedure carried out in and by the hardware/software of the laser system. As illustrated schematically by the laser system 10 in FIG. 1, some type of diagnostic input 12 from a surgeon and/or one or more diagnostic devices 14 is sent to a laser platform 16. The laser platform includes a computer-linked control system 18 that utilizes software to compute an appropriate laser ablation shot file based upon optical zone size and other input parameters entered by the surgeon. The laser platform also includes hardware in the form of beam shaping and steering optics that react to instructions from the control system to deliver the shot file in the appropriate manner to the cornea. Thus, the laser platform is a xe2x80x9csmartxe2x80x9d device, so to speak, because it is there that both information processing and treatment execution occur. In an aspect shown by the dotted lines, the laser platform is capable of receiving a computer-readable medium 20 having both enablement and instructional software stored therein which can be processed by the computer system in the laser platform.
Certain disadvantages attach to the methodologies such as those described above. In the first case described, the laser platform is burdened with computer hardware and software adding to the complexity and cost of every unit. In the second scenario described above, the computer-readable medium may be in the form of a single use enablement card, for example, as described in U.S. Pat. Nos. 6,296,634 and 6,364,873. Such enablement cards are typically purchased by a user, and generate a set per-procedure fee for the laser manufacturer. Each treatment procedure requires a card, while the laser system continues to require the necessary computer hardware and software as mentioned above. Thus the laser system lacks flexibility and is no less burdened than described above. Moreover, there are many aspects of the laser platform that can malfunction, increasing the risk of surgical downtime for the user. Trained technicians having skills in multiple technical fields are required to maintain and service the multi-component laser platforms.
In view of the foregoing and other disadvantages currently associated with typical laser vision correction systems, the inventors have recognized a need for improvements that increase the flexibility and reduce the cost of making, supplying, maintaining, and controlling laser vision correction systems, and which make it easier for the surgeon to provide the best treatment outcomes for their patients.
The invention is generally directed to apparatus and methods involved in the control of a laser vision correction system, and a system incorporating these controls.
An embodiment of the invention is directed to a device-readable medium on or in which is stored a pre-programmed, readable, first corrective instruction reference. This instruction reference corresponds to an encoded customized corrective instruction. As used herein, the term xe2x80x9ccustomized corrective instructionxe2x80x9d refers to the number, sequence, and placement of laser pulses for a particular laser vision correction treatment. The instruction is determined by a calculation module located external to the medium and to the laser platform, and is executable by the laser platform of a laser vision correction system. The customized corrective instruction is determined in a manner that will be described in greater detail below. A particular customized corrective instruction is then encoded in such a manner that the instruction can be executed by the laser platform upon recognition of the corresponding instruction reference stored in or on the medium. In an aspect of this embodiment, the first corrective instruction reference stored in or on the medium is a necessary and sufficient component for enabling the laser platform to execute the customized instruction when the instruction reference is properly recognized. In an alternative aspect, the first instruction reference is a necessary but not sufficient component for allowing enablement and execution of the customized instruction by the laser platform. Rather, a second, readable corrective instruction reference is stored in or on the medium and in combination with the first corrective instruction reference, is sufficient for enabling execution of the customized instruction. Preferably, the second instruction reference will correspond to an encoded user ID or laser platform ID which will be associated with the customized instruction. In an alternative aspect, the medium may have stored therein a second pre-programmed instruction reference and a third pre-programmed instruction reference, corresponding to a user ID and a laser platform ID, in addition to the first instruction reference corresponding to the customized corrective instruction. In this aspect, all three matching instruction references are necessary and, in combination, sufficient components for enabling the execution of the customized instruction by the laser platform. With respect to all of the aspects referred to above, the total data storage requirement for any or all of the instruction references in combination, along with any other information stored in the medium, preferably will not exceed 1000 bytes of storage space. In another aspect according to this embodiment, the medium includes a laser platform disablement feature that limits a preset number of uses of the laser platform for each readable medium unit. This feature provides an annuity structure for laser system use as is well known in the art. In a further aspect, the medium includes a beam sizing and shaping feature to provide a desired beam diameter and beam energy profile for ablating a corneal surface and/or facilitating beam diagnostics.
In another embodiment according to the invention, a laser vision correction system includes a calculation module that can receive input data relating at least to a refractive defect of a patient""s eye and calculate a customized corrective instruction based, at least in part, upon the input data. As used herein, the term calculation module refers either to a hardware device, computer-executable software which performs all pertinent aspects of an ablation treatment algorithm, or a combination of hardware, software, and/or firmware for determining the customized corrective instruction. The calculated customized corrective instruction is then encoded such that the encryption will allow a matching correspondence to a pre-programmed first corrective instruction reference that is stored in or on a device-readable medium. The system further includes a laser platform that can receive the readable medium and execute the customized corrective instruction, as a necessary condition, only when the first corrective instruction reference corresponding to the encoded customized corrective instruction is recognized by the laser platform. The calculation module is external to the laser platform and preferably resides in a diagnostic platform that is used to generate at least some of the input data. In a preferred aspect of this embodiment, the customized corrective instruction calculated by the calculation module may include more than one particular corrective instruction for each of a variety of laser vision corrective treatments. For example, depending upon the input data, the calculation module may generate three different corrective instructions for myopia treatments, or, two different instructions for hyperopia treatments, that, when encoded, correspond to the first corrective instruction reference on the storage medium, thus potentially providing the user with a choice of appropriate treatment options. In a related aspect, the system includes a graphical user interface (GUI) that is operably associated with the laser platform, along with a configuration file that is also operably associated with the laser platform and the GUI. In this aspect, the configuration file will recognize the instruction reference corresponding to the customized corrective instruction and will then initiate a particular GUI associated with the one or more matched, customized corrective instructions. The GUI will then allow the user to input information that will result in the selection of a single matching instruction reference recognized by the configuration file in the laser platform that will enable and allow the laser platform to execute the particular customized refractive instruction.
In another embodiment, a method for controlling a laser vision correction system includes providing a device-readable medium having the attributes of the device-readable medium set forth hereinabove, for use in a laser platform to execute a particular laser vision correction procedure. It further includes providing the medium to a third party on a remunerative basis; and, structuring the remuneration as a function of type and/or number of corresponding instruction references supplied in the medium.
Another method embodiment for controlling a laser vision correction system involves determining a customized corrective instruction for correcting an ophthalmic refractive defect, encoding the instruction, providing a transferable device-readable medium that includes a pre-programmed, first corrective instruction reference which corresponds to the encoded instruction, and providing a laser platform that can receive the transferable medium and recognize the corresponding first instruction reference as a necessary condition for enabling execution of the customized corrective instruction. In a preferred aspect, the method further includes providing a GUI that is operably connected with the laser platform and which is configured according to the instruction reference corresponding to the encoded instruction. In a further related aspect, the method includes providing either or both of an encoded user ID and an encoded laser platform ID, and providing associated second and/or third corresponding instruction references in the transferable medium which are recognizable as necessary and, perhaps, sufficient conditions for allowing execution of the customized corrective instruction. In addition to, or in place of, the second and/or third instruction reference, other corresponding codes can be stored in the medium; e.g., iris pattern codes. The medium storage structure may further be writeable such that the medium could be inserted into a component of the diagnostic platform to directly receive specific encoded or uncoded data.